Origin and diffusion
The tomato is a Solanaceae native to south-western America (Chile, Ecuador, Peru) which only began to be used in Italy as a condiment at the beginning of the 19th century and which began to be industrially transformed at the end of the same century. Previously it was considered inedible.
Annual production in Italy is approximately 128,000 hectares with an average production of 54 t/ha, 15% destined for fresh consumption and 85% for the canning industry for concentrates, peeled, crushed, puréed, etc. Out-of-season production for fresh consumption has significant economic importance with around 6,000 ha of greenhouse cultivation.

The plant normally reaches a height ranging from 50 cm to 2 m. It has down on both the stem and the leaves and is erect or sarmentose (depending on the type of crop chosen).
The flower usually grows on the side opposite the leaf and takes on a yellow goblet shape. The tomato berry - of variable shape, size and color depending on the variety - has a smooth skin and a fleshy pulp with an internal division into lodges, containing the flattened circular-shaped seeds of a white-yellow colour.

The various types of tomato are divided both based on the shape of the berry and based on its final use.
They can be:
– round;
– pear shape;
- Oval;
– ribbed;
– in bunches.

Depending on the final use, you can have table tomatoes, concentrate tomatoes, juice tomatoes and peeled tomatoes.
Generally the varieties recommended for the vegetable garden are those for the table and for preserves, both for the type of cultivation and for the type of use.
The varieties that are recommended for fresh use are the following:
Ace, round. Sowing February/April. Harvest June/September climbing habit. Ausonio, Tondo, sowing February/April. Harvest June/September climbing habit. Monte Carlo, Tondo Sowing February/April Harvesting June/September climbing habit. S. Marzano (Perino) Sowing February/April. Harvest June/September, climbing habit. Roma (Perino) sowing February/April, harvesting June/September, low growth habit. Cuore di Bue (Costoluto) Sowing February/April, harvesting June/September climbing habit.
The Rio Fuego, the Canestrino di Lucca, the Brandywine and the Double Rich are also excellent.
The tomato plant cannot resist low temperatures. For this reason cultivation is carried out in the spring-summer period. In the southern regions, cultivation can be brought forward by a month or two depending on the climatic conditions. It can also be grown in a greenhouse or tunnel, and in this case it can be grown all year round.

Plant
Tomato crops can be established by sowing in the field or by transplanting. The first system is spreading in open-air cultivation, the second is the exclusive one in greenhouse cultivation and is still widely used even in open field.

Seedbed
Transplanting requires the production of seedlings in a seedbed which is mostly protected to ensure the right temperature for germination.
Sowing can be done by broadcast on the seed bed, or by single seed in containers (phytocells, alveolar panels) or in cubes of soil; in the first case the plants are transplanted with bare roots, in the other cases with earthen bread.
Sowing in seedbeds ensures various advantages: saving time, greater earliness, greater uniformity, seed saving.

Sowing in seedbeds is done at different times according to the type of cultivation you want to do: autumn-early winter for greenhouse crops; winter for early, temporarily protected crops; late winter (February-March) for full season field crops; summer for late cycle crops.

From 1 square meter of seedbed, 500-600 seedlings suitable for transplanting can be obtained, for which 2-3 grams of seed must be sown corresponding to 600-900 seeds per square meter. for each hectare of cultivation, 60-80 square meters of seedbed are required, considering planting densities of 3500-4500 plants per hectare.

Transplant
After 40-60 days from sowing the tomato seedlings reach the stage of 4-5 leaves and a height of 100-150 mm: this is the best time for transplanting.
In open-field crops of industrial tomatoes, transplanting is done from mid-April to mid-May. In the open field, a widely used type of system is the twin row system, which will be discussed later in relation to direct sowing.

The transplant is done by hand or by machine; Plants with earthen bread grown in honeycomb containers adapt well to this last system.

Direct sowing. Direct sowing tends to extend into open field cultivation because it has the advantage of reducing planting costs and giving rise to vigorous plants, especially in the root system, as they do not have to overcome the transplant crisis.
The negative aspects are: greater quantities of seed are consumed, the seedbed must be prepared with great care, a certain thinning may sometimes be necessary, sowing cannot be done before the temperature has reached the minimum necessary value (12° C approximately) to ensure acceptably ready germination and emergence.
The tomato can be sown with an excess of seed (1-1.5 kg/ha) postponing the elimination of the excess plants until thinning; or 0.4-0.5 kg/ha of seed can be sown with a precision seeder, in which case thinning can be omitted.

Distances
it can be done in simple rows 1-1.5 m apart, but it is mostly done in double rows with 0.30-0.40 m between the rows of the double rows and 1.3-1.5 m between the double rows.
The twin row is advantageous in several respects:
– Better shading of the berries by the foliage;
– Less branching and greater maturation at the same time due to the strong competition between the plants of the bin;
– Lower cost of the drip irrigation system (rather widespread) due to the lower linear development of the drip lines;
– Greater ease of mechanical harvesting.

The desired investment varies from 3 plants per m2 in the case of single row cultivation to 6-8 in the case of twin rows.
The sowing depth must not be excessive: given the smallness of the seeds, it should not exceed 20-30 mm.

When the precision seeder is used, the regularity of sowing is advantaged by the coating of the seeds whose tormenting surface would tend to cause them to agglomerate.

Tomato sowing in the open field is done in spring: around March in the milder environments of the South, in April in the Centre-North.

Cultural care
When transplanting, auxiliary irrigation is always necessary to ensure rooting. After sowing, rolling can be useful to encourage seed soaking and germination.

Compensation for transplant failures and thinning may be necessary to ensure the right investment. Weeding is advisable not only to control weeds, but also to aerate the soil and reduce evaporation.

In many cases, mulching with black plastic films is practiced, today also with Mater-B: generally it is associated with a type of twin-row system and "drip" irrigation. The dripline is placed in the center of the bin, below the mulching film. The high costs are compensated by significant agronomic and qualitative advantages (cleanliness of the product).

The installation of supports is necessary in the case of greenhouse varieties or certain vegetable garden varieties (San Marzano) with indeterminate development. In these same varieties some particular operations are practiced such as: trimming to eliminate the axillary shoots and thus maintain a single-stemmed plant; trimming, trimming the plant leaving 3-6 fruiting stages in order to favor the ripening of the fruits on the stages left.

Frequent, light watering is preferable for table tomatoes; for industrial crops, less frequent and more abundant irrigation is more suitable, taking care to do the last irrigation well in advance of harvesting; in case of limited water availability, some water savings can be made during the vegetative phase and during the maturation phase, but it is important that the water does not fail during the flowering phase.
Improper water management can cause damage to sensitive varieties such as blossom end rot, fruit splitting and sunburn.

Avoid sprinkler irrigation systems which favor fungal diseases and bacterial cancer); traditionally the lateral infiltration system is one of the most used, while the drip system is becoming more widespread: both have the advantage of not wetting the vegetation.

Fertilization
It is important to precede the tomato in the rotation with a crop of legumes and even better with a green manure.

Fertilization must be commensurate with the productivity of the crop and the soil's supply of organic matter.
In the case of greenhouse crops, very intensive and capable of giving very high productions of 80 -120 t/ha and even higher.
In the case of open field crops, productivity is lower than that in a greenhouse, but here too a distinction must be made between dry and irrigated crops.

In irrigated cultivation the expected production is of the order of 60 – 80 t/ha and organic fertilization must be done by calculating 150-180 Kg/ha of N, 80 Kg/ha of P2O5, 150 Kg/ha of K2O; Considerably reduced doses are to be expected in dry crops whose production is around 20-30 t/ha.
Given the particular nitrogen requirements, ox blood and slaughterhouse waste such as bones, hoofs and horns are also used in the compost.

The preparation of the soil is very important given that the crop will remain planted for several months. The structure must be very loose and fertile. An excess of undecomposed organic substance can be a source of root rot: for this reason fertilization with fresh manure is rarely carried out but fertilization with mature compost is preferred.
The tomato has a climbing habit and for this reason a support is needed to support it. The brace must be sturdy enough as it will have to support the weight of the tomatoes. The transplant is usually carried out in the month of April/May in the north while it is brought forward by a month in the center and south. It is important, after transplanting, to keep the soil clean from too many weeds. It is also advisable to carry out a light earthing to cover the roots that emerge from the ground. Watering must be abundant and regular.
A very important operation is pruning, which consists in removing the secondary shoots to favor the main shoot.
The harvesting of tomatoes varies according to the area in which we are located, usually the table tomatoes are harvested semi-ripe to increase conservation.

Cryptogamic diseases
Downy mildew (Phytophtora infestans). It affects the leaves, stem and fruits, invading the tissues and forming a whitish mold. It is necessary to treat with copper-based preventive or curative products
Alternariosis forms rounded necrotic spots with a well-defined outline and concentric zoning on the leaves and causes lesions and narrowing of the collar on the stem. It is necessary to use healthy seed; anti-downy mildew treatments generally serve to control this disease as well.

The root system can also be severely affected. In particular, there are two most widespread fungal diseases: root rot and collar rot. The fruit and leaves are also affected and there may be reddish amber spots on the leaves, and circular blisters on the dark green fruits. To prevent some of these diseases it is necessary to pay particular attention to the quantities of fertilizer and water we administer to our plants. Regular water balance is of particular importance, which is why it is not recommended to let the soil dry out excessively and then soak it to try to remedy this.

Animal parasites
The most dangerous parasites for tomatoes present in the soil are the Colorado potato beetle and potato nematodes which cause a lot of damage to the roots of the tomato.
There may be attacks by aphids which, in addition to damaging the plant's tissues, cause the leaf to curl and are also vectors of viruses. To prevent and combat these parasites it is advisable to spray with pyrethrum, with a very low withdrawal period and allows the plants to be treated even a few days before harvest.
Occasionally there may be attacks by noctules and wireworms that gnaw at the collar of the seedlings.
Root-knot nematodes also tend to spread when rotation is not respected.

Biodynamics
The stimulus of the horn manure is fundamental in the early stages of vegetation and subsequently to keep the circulation of the sap constantly regulated.
Cornsilica helps color, strong flavor and preservation of fruits.

Prevention with horsetail tea can begin as a seed dip upon transplanting and continue in the following weeks.

Excellent results with macerates of the stem and leaves of the tomato crop preserved from the previous year's crop and with nettle macerate.